Humic Substances, Part 9: Biomedical Applications

Humic substances produced on a commercial scale are used in veterinary and human medicine. Several studies of the medicinal properties of humic materials have been reported (Mund-Hoym 1981, Brzozowski et al. 1994). It was found that humic acids administered prophylactically to rats decreased significantly the extension of gastric damage induced by ethanol. TPP administered to rats with experimental gastric and duodenal ulcers significantly accelerated the healing process (Brzozowski et al. 1994)
Pflug and Ziechman (1982) reported that humic acids are able to interact with the bacterium Micrococcus luteus. In this case humic materials protected the organism against cell-wall disruption by the enzyme lysozyme. Thiel et al. (1981), who found that preincubation of cell cultures with ammonium humate avoided infection by the herpes virus, noted the function of humic substances as protectors of the organism.

In the last decade there has been an increasing interest in the employment of humic materials in medicine and biology. The possibility of soil humus extract with amino acid complexes and vitamin B analogues being a candidate as a base of cosmetic and pharmaceutical products has been studied. The main reason for the increasing attention devoted to humic acids can be explain by their antiviral, profibrinolytic, anti-inflammatory and estrogenic activities (Yamada et al. 1998). The potential of humic substances to form chelate complexes with heavy metals (such as cadmium) enable them to be used for the elimination of heavy metals from living organisms (Klöcking 1992). Humic materials in aquatic systems and water sediments have been observed to be closely connected with efficacy of hydrotherapy and balneotherapy (Gadzhieva et al. 1991, Hampl et al.

1994). Antibacterial (Ansorg 1978, Skliar et al. 1998) and antiviral (Klöcking and Sprossig 1972, Thiel et
al. 1977 1981, Schiller et al. 1979, Klicking 1991, Klöcking et al. 2002) properties of humic substances represent new possibilities for their medical application.

Of great interest is that hospital studies show that difficult viral respiratory illnesses common in children are readily resolved with fulvic acid dietary supplementation. Fulvic acid is a humic extract common to rich organic humus soil and also certain ancient plant deposits. Many medical studies show that humic substances, especially fulvic acids, have the power to protect against cancer and related cancer-causing viruses. Studies often show reversal of deadly cancers and tumors using special humic substance therapies (Schneider et al. 1996, van Rensburg et al. 2002, Joone et al. 2003).

On the other hand, humic acid has been shown to be a toxic factor for many mammalian cells, but the specific mechanism of its cytotoxicity remains unclear. Its redox properties make humic acid capable of reducing iron(III) to iron(II) in aqueous conditions over a broad range of pH values (from 4.0 to 9.0) and of reducing and releasing iron from ferritin, but this process is partially inhibited by superoxide scavengers. Subsequently, the iron released from ferritin has been shown to accelerate the humic acid-induced lipid peroxidation. Humic acids have the ability to reduce and release iron from ferritin storage as well as to promote lipid peroxidation. Therefore, HAs coupled with released iron can disturb the redox balance and elicit oxidative stress within a biological system. This may be one of the most important mechanisms for HA-induced cytotoxicity (Ho et al. 2003). Humus represents one of the greatest carbon reservoirs on the Earth. Although industrial applications of humus and humus-derived products were a relatively low scale, usage of coal was more abundant and was the basis of the chemical industry in the second half of the 19th century and in the first half of the 20th century. Petroleum was also applied and it is considered as the main raw material for the chemical industry of the 20th century (Ghabbour and Davies 2001). 

Now it is time for new applications of humic substances in less traditional arenas, mainly in biomedicine (Laub 1999, Laub 2003a, Laub b, Ghosal, 2003).